TWI258778B

TWI258778B - Variable capacitor and manufacturing method thereof

Info

Publication number: TWI258778B
Application number: TW093116141A
Authority: TW
Inventors: Takeaki Shimanouchi; Masahiko Imai; Tadashi Nakatani
Original assignee: Fujitsu Ltd
Priority date: 2004-05-31
Filing date: 2004-06-04
Publication date: 2006-07-21
Also published as: US20070025050A1; DE112004002785T5; DE112004002785B4; US7446994B2; JPWO2005117042A1; TW200539204A; CN1947209B; WO2005117042A1; CN1947209A; JP4571127B2

Abstract

A lower movable electrode having line parts on the opposite end sides and a capacitor part on the central side, and an upper movable electrode having line parts on the opposite end sides and a capacitor part on the central side are arranged such that the capacitor parts face each other. Driving electrodes of actuators for driving the lower movable electrode and actuators for driving the upper movable electrode are provided so as to be isolated electrically from the lower movable electrode and the upper movable electrode. Electrostatic capacity is controlled by moving the lower movable electrode and/or the upper movable electrode through the actuators and/or thereby adjusting the distance between both capacitor parts.

Description

1258778 坎、發明說明：【發明所屬之技術销域】本發明係有關於一種可變電容器及其製造方法，尤其疋有關於種使用MEMS (微機電系統；MiCr〇 Electro Mechanical System)技術且具有相對向之可動電極之可變電容器及其製造方法。1258778 kan, invention description: [Technical sales field to which the invention belongs] The present invention relates to a variable capacitor and a method of manufacturing the same, and in particular to a MEMS (Micro Electro Mechanical System; MiCr〇 Electro Mechanical System) technology and having a relative A variable capacitor to which a movable electrode is applied and a method of manufacturing the same.

【先前J 可變電容器係於可變頻率振盪器、調諧放大器、移相器、阻抗匹配電路等在内之電性電路中位居重要之零件，近年來’其裝載於攜帶型機器之機會漸增。和目前主要使用之變容器二極體相比，利用MEMS技術而製造之可變電各器具有損失較小，且使Q值較高之優點，正大力致力於該電容器之研發。第1〇)、1(b)圖係顯示習知可變電容器結構之剖視圖 15及俯視圖（參考諸如非專利文獻1)。該可變電容器之構造為：將具有單壓電晶片（unimorph)型壓電致動器12及可動電極13之可動電極用基板η、設有固定電極16之固定電極用基板15在可動電極13及固定電極16相對之狀態下，以軟焊墊14接合者。藉壓電致動器12之驅動，使可動電 2〇極13移動，改變可動電極13與固定電極16間之距離，以控制電容器之容量。[Previously J variable capacitors were important components in electrical circuits such as variable frequency oscillators, tuned amplifiers, phase shifters, and impedance matching circuits. In recent years, their chances of being loaded on portable machines have gradually increased. increase. Compared with the varactor diodes currently in use, varistor devices manufactured by MEMS technology have the advantages of less loss and higher Q value, and are actively working on the development of the capacitor. Figs. 1 and 1(b) show a cross-sectional view 15 and a plan view of a conventional variable capacitor structure (refer to, for example, Non-Patent Document 1). The variable capacitor is configured such that the movable electrode substrate η having the unimorph type piezoelectric actuator 12 and the movable electrode 13 and the fixed electrode substrate 15 provided with the fixed electrode 16 are on the movable electrode 13 When the fixed electrode 16 is opposed to each other, the solder pad 14 is joined. By the driving of the piezoelectric actuator 12, the movable electric 2 dipole 13 is moved to change the distance between the movable electrode 13 and the fixed electrode 16 to control the capacity of the capacitor.

【非專利文獻 1 】Jan Y· Park, etal·，nMICROMACHINED RF MEMS TUNABLE CAPACITORS USING PIEZOELECTRIC ACTUATORS' IEEE International Microwave Symposium, 2001 1258778 惟，依上述之習知可變電容器，乃有如下之問題。以軟焊墊14將可動電極13及固定電極16相接合，導致兩電極間之距離是以軟焊墊14控制，不能將該距離縮小到為〇之接近狀態，使壓電致動器12處於初始狀態時之電容器之 5 靜電容量增大。電容器之靜電容量C與用以構成電容器之電極間的距離d之間具有C= £〇£r S/d (e〇:真空的介電常數、相對介電常數、S :電極面積）之關係，將靜電容量c及電極間距離d之關係示於第2圖。第2圖中，縱軸與橫軸的 10 刻度以初始狀態C及d規格化。壓電致動器之變化量為固定時，兩電極相靠近之狀態下之靜電容量的變化比例較分開之狀態還大。因此，初始狀態時之靜電容量不能增大(較小）意指靜電容量的變化亦不能增大(較小）。如第1(b)圖所示，在該習知例之可變電容器中，以扭 15桿17連接可動電極13與壓電致動器12,使可動電極13 及壓包致動為12用之驅動電極一體構造而成，且呈電性連接。但迄至用以構成電容器之可動電極13之前的線路含有一見度狹小之扭桿17，因此具有如下問題，即，該部分形成等效串聯電阻（ESR ·· Equivalent Series Resistance)， 2〇而發生電阻損失，並且因為兼用為與可變電容器電性連接之^號線路及壓電致動器12用之驅動電極，所以該信號線路包體之壓電元件相接觸，而產生介電損失，使Q 值變得極小者。又，迄至可動電極13之前的線路不能進行阻抗匹配，亦導致業已輸入之能量損失，即***損失。在 1258778 此，本發明人致力於可解決前述問題之技術研發。此外，本發明人有一可變電容器之提案，其構造成：可以壓電致動器驅動相對之兩電極之任一者（日本專利公開公報：特開2004-127973號）。如此形成兩個可動電極相 5對之構造的可變電容器並沒有設置凸出部，可輕易縮小兩電極間之距離，因此可展現如下效果，雖為小型構造，亦可獲得較大之靜電容量，且使靜電容量變化加大者。【發明内容】本發明係有鑑於上述問題點而所構建成者，其目的在於提仏種可變電谷态及其製造方法，該可變電容器即使為】里、、、°構亦可將靜電容量加大，且使靜電容量變化的比例變大，亦可做到靜電容量之微調整，且Q值亦高者。本發明之另一目的係於提供一種可變電容器及其製造方法，可防止由外部輸入之信號所發生之能量損失(*** &本發明之另一目的係於提供一種可變電容器及其製 k方法，即使壓電致動器的驅動電壓小，，亦可獲得較大之靜電容量及靜電容量較大變化者。本發明之可變電容器，其特徵在於相對之電極可之可變電容器中’包含有··基板、具有第i電極部及第2 電極部之可動電極、及，狀|_前述可動電極之多數芦電致其中前述可動電極相對設置以構造成電容器，將幻述可動電極與信號墊導電連接者。本^明’將可動電極及用以雜可動電極之壓電致 20 1258778 動器設於同一基板，因此為小型結構。又，因為可將各可動電極移動，所以可將兩可動電極間之距離縮小，實現較大的靜電容量及靜電容量之較大變化，靜電容量之微調整亦較為容易。又，相當於迄至用以構造成電容器之第2電 5 極部之線路(信號線)之第1電極部與用以驅動壓電致動器之驅動電極呈電性分離之狀態，因此可使第1電極部不接觸於壓電致動器之壓電體（高介電體），抑制***損失，以謀求Q值提昇者。本發明之可變電容器，其中前述可動電極係包含有前 10 述第1電極部及第2電極部，且將前述可動電極上下設置者。依本發明，相當於迄至用以構造成電容器之第2電極部之線路之第1電極部中，不含有如習知例之寬度狹窄之扭桿，可縮小等效串聯電阻，因此可謀求Q值之提升。 15 本發明之可變電容器之特徵係於：其中前述多數壓電致動器各自具有驅動電極及設於該驅動電極間之壓電元件，前述驅動電極與前述可動電極為互不相干之個體者。依本發明，使電容器用之可動電極與壓電致動器用之驅動電極為互不相干之個體構造，因此不會像習知例般之 20 線路部接觸於壓電元件（高介電體），且謀求Q值之提升。本發明之可變電容器之特徵在於：其中前述可動電極之第1電極部兩側設置前述壓電致動器，藉前述第1電極部及前述壓電致動器之驅動電極，構造成一 CPW型線路 877; ................................................................ 声依本發明，藉調整CPW型線路中之第i電極部之寬 ^與第1電極部及壓電致動器之驅動電極間之間隔，可輕進行阻抗匹配，因此沒有***損失，可謀求Q值之提升7 5 之本發明之可變電容器之特徵在於：其中前述可動電極之相對之前述第2電極部間設有介電體層者。 ^依本發明，在用以構成電容器之第2電極部間設有介電體層’因此可謀求靜電容量及其變化量之進—步的增大。 10 η本务月之可、交電谷裔之特徵在於：其係使前述可動電極中之至少一方與接地電極相連接者。、依本發明，藉使-方之可動電極與接地電極相連接，以可抑制浮動容量。之本毛月之可麦電谷為之特徵在於··其中前述可動電極之任—方的前述第丄電極部與前述第2電極部間之境界部近旁係呈電性分離者。 15 依本發明’因為一方之可動電極在第i電極部愈第2 _部間之境界部近旁呈電性分離之狀態，所以朝一方之弟二電極部輪入之信號通過第2電極部，最後到達另一方 =二電=部之端’使之沒有在此反射之情況，減低輸人仏唬之此1損失(***損失）。本發明之可變電容器，其特徵係於包動該可動電極之麼電致動 ::裝置俾:：對前述可動電極間施加電壓之電壓施動電極相接近==壓電致動〜，使前述可之狀恶下’猎可述電壓施加裝置，將電壓施 20 1258778 加於前述可動電極間者。依本發明，藉壓電致動器之驅動，接近之狀態下，在—對可動電極間施加電壓日^電⑽目可動電極間所產生之靜電吸力，將糟一對加縮小者。之距離更本發明之可變電容器之製造方法’該。〆麼電致動器的驅動以使電極呈可移動之狀態：，：=藉 10 15 20 :徵係於包含有以下步驟，:在基板上形成多數前述：電致動器之步驟；在前述基板形成具有第i電極部ζ 電極部之可動電極之步驟；形成—用以於前述可動電形成間隙之犧牲層之步驟；將前述犧牲層除去之除去二驟；及’將除前述多數前述壓電致動器之端部及前1 = ==1電極粒㈣之外㈣分” «板切離之切依本發明，便可輕易地在同一基板上形成極及用以驅動前述可動電極之壓電致動器。电 ”本發明之可變電容器之製造方法，該可變電容器堡電致動器的驅動以使電極呈可移動之狀態者1方去曰 Γ係於包含有以τ步驟在基板上形成从前;^ 电致動仏步驟；在前述基板形成具有第i電極部及第2 電極部之可動電極之步驟；在前述可動電極間形成介電體 =步驟；形成—用赠前述可動電極之任—方與前述^ 电體層間形成間隙之犧牲層之步驟；將前⑽牲層除去之除去步驟；及，將除前述多數前述壓電致動器之端部及前 10 U58778 " 1極之帛1 ^極部之端部之外的部分由前述基板切择之切離步驟。柄、依本發明’便可輕易地在同-基板上形成-對可動電用Μ驅動刖述可動電極之壓電致動器及一對可動間之介電體層。位本發明之可變電容k製造方狀龍錄：去步驟及前述切離步驟同時進行者。牙、、本^%可使除去犧牲層之除去步驟及將除端部外 10 鲁 ί可動電極及壓電致動器由基板切離之切離步驟同時進仃，因此可提昇作業效率。守進按本發明，可提供— /、種可變電容器，其耐衝擊性佳，結構’亦可將靜電容量加大，且可將靜電容量之夂化比例加大，亦可進彳Λ h 之 ^ 笔各量之微調整者。又，使 15 =與壓電致動器呈電性分離之狀態，：效串聯電阻原因所在之扭桿的構进成為專 (第2電極部)之前確保寬纟冱至電谷态形成部得到高Q值者。一線路部…電叫因此可又，按本發明，將電成由基板浮在空中之狀#〜^分及其周圍部分構建 …，可得到高二，因此消除基板等之介電常數的又，按本發明，將一方可織$ 與第2電極部間之境界構造成在第1電極部由外部輸入之信號的能量損失(插者，因此可防止進而，按本發明，構建成：藉壓電致動器之驅動俾使 11 1258778 5 10 15 20 一對可動電極相接近之狀態下，在一對可動電极門^力h 壓者，可藉一對可動電極間所產生之靜電吸力， ^ 將兩可勤電極間之距離更加縮小，且可得到較大之靜電办I I ®及靜電容量較大的變化。又，藉壓電致動器之驅動，使—對^ 電極相接近之狀態下，產生靜電吸力’因此可 W較小的驅動電壓，產生較大之靜電吸力。【實施方式】參考顯示本發明實施形態之圖式，具體說明本發月此外，本發明並不限於如下之實施形態者。又 (弟1實施形態）第3圖係第1實施形態之可變電容器之 ^ 兀體圖；第4 圖係該分解立體圖。圖中，標號21為以矽、化入物半、:一等形成之基板。在基板21中央部設有十字形開口、導體基板21之上面設有絕緣層23。且在圖中，標號35、37各為以A1(鋁）構成之下立口極、上部可動電極。下部可動電極35係由作為第卩Z動電之兩端側線路部35a、35a及作為第2電極部之中二电裔部35b所構成，一方的線路部35a之端部係與用J私谷部之高頻信號源(圖中未示)輸入信號之信號墊45、相以由外而另方的線路部35a之端部則連接於絕緣層幻、接地電極44呈電性分離者。在其等端部上，，且與 35係支撐於基板η，除其^部狀下部作Y動電極其餘部分則位於開口 40上。又，上部兒° 35之 FT動電極37係由作為弟1 %極部且位於兩端側之線路、 /a及作為第2[Non-Patent Document 1] Jan Y. Park, et al., nMICROMACHINED RF MEMS TUNABLE CAPACITORS USING PIEZOELECTRIC ACTUATORS' IEEE International Microwave Symposium, 2001 1258778 However, according to the above-described conventional variable capacitor, there are the following problems. The movable electrode 13 and the fixed electrode 16 are joined by the solder pad 14, so that the distance between the electrodes is controlled by the solder pad 14, and the distance cannot be reduced to the close state of the crucible, so that the piezoelectric actuator 12 is at In the initial state, the capacitance of the capacitor 5 increases. The relationship between the electrostatic capacitance C of the capacitor and the distance d between the electrodes constituting the capacitor has a relationship of C= £〇R S/d (e〇: dielectric constant of vacuum, relative dielectric constant, S: electrode area) The relationship between the electrostatic capacitance c and the distance d between the electrodes is shown in Fig. 2. In Fig. 2, the 10 scales of the vertical axis and the horizontal axis are normalized in the initial states C and d. The amount of change in the piezoelectric actuator is fixed, and the ratio of the change in electrostatic capacitance in the state in which the two electrodes are close to each other is larger than the state in which the separation is performed. Therefore, the electrostatic capacity at the initial state cannot be increased (small) means that the change in electrostatic capacity cannot be increased (smaller). As shown in Fig. 1(b), in the variable capacitor of the conventional example, the movable electrode 13 and the piezoelectric actuator 12 are connected by a twist 15 rod 17, and the movable electrode 13 and the press pack are actuated to 12 The driving electrodes are integrally formed and electrically connected. However, the line before the movable electrode 13 for constituting the capacitor contains the torsion bar 17 which is narrow in visibility, and therefore has a problem that the portion forms an equivalent series resistance (ESR · · Equivalent Series Resistance) Since the resistance is lost, and since it is used as the driving electrode for electrically connecting the variable capacitor and the piezoelectric actuator 12, the piezoelectric elements of the signal line package are in contact with each other to cause dielectric loss. The Q value becomes extremely small. Further, the line up to the movable electrode 13 cannot be impedance-matched, and the energy loss that has been input, that is, the insertion loss, is also caused. At 1258778, the inventors of the present invention have been working on a technology development that can solve the aforementioned problems. Further, the present inventors have a proposal of a variable capacitor which is configured such that a piezoelectric actuator can drive either of the opposite electrodes (Japanese Patent Laid-Open Publication No. 2004-127973). The variable capacitor having the two movable electrode phases formed in this manner is not provided with the protruding portion, and the distance between the electrodes can be easily reduced, so that the following effects can be exhibited, and even a small structure can obtain a large electrostatic capacity. And increase the electrostatic capacity. SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object thereof is to provide a variable electric valley state and a manufacturing method thereof, and the variable capacitor can be constructed even if it is The electrostatic capacity is increased, and the ratio of the electrostatic capacitance change is increased, and the electrostatic capacity can be finely adjusted, and the Q value is also high. Another object of the present invention is to provide a variable capacitor and a method of manufacturing the same that can prevent energy loss from externally input signals (insertion & another object of the present invention is to provide a variable capacitor and its system In the k method, even if the driving voltage of the piezoelectric actuator is small, a large electrostatic capacitance and a large electrostatic capacitance can be obtained. The variable capacitor of the present invention is characterized in that the variable capacitor is opposite to the electrode. The substrate includes a movable electrode having an i-th electrode portion and a second electrode portion, and a plurality of reeds of the movable electrode, wherein the movable electrode is disposed opposite to each other to form a capacitor, and the movable electrode is patterned. The conductive electrode is electrically connected to the signal pad. The piezoelectric electrode 20 1258778 actuator for the movable electrode and the micro movable electrode is provided on the same substrate, so that the movable electrode can be moved. The distance between the two movable electrodes is reduced to achieve a large change in electrostatic capacitance and electrostatic capacitance, and the micro-adjustment of the electrostatic capacitance is also relatively easy. The first electrode portion of the line (signal line) for configuring the second electric 5 pole portion of the capacitor is electrically separated from the driving electrode for driving the piezoelectric actuator, so that the first electrode portion can be made The piezoelectric capacitor (high dielectric) that does not contact the piezoelectric actuator suppresses insertion loss and improves the Q value. The variable capacitor of the present invention, wherein the movable electrode includes the first electrode of the first ten In the second electrode portion, the movable electrode is placed up and down. According to the present invention, the first electrode portion corresponding to the line for the second electrode portion configured as a capacitor does not include the conventional example. The torsion bar having a narrow width can reduce the equivalent series resistance, so that the Q value can be improved. 15 The variable capacitor of the present invention is characterized in that the plurality of piezoelectric actuators each have a driving electrode and are disposed on the driving In the piezoelectric element between the electrodes, the drive electrode and the movable electrode are independent of each other. According to the present invention, the movable electrode for the capacitor and the drive electrode for the piezoelectric actuator are independent of each other. The 20-circuit portion is in contact with the piezoelectric element (high dielectric) as in the conventional example, and the Q value is improved. The variable capacitor of the present invention is characterized in that both sides of the first electrode portion of the movable electrode are The piezoelectric actuator is provided, and the first electrode portion and the driving electrode of the piezoelectric actuator are configured as a CPW type line 877; .................. .............................................. Sound according to the invention By adjusting the interval between the width of the i-th electrode portion in the CPW-type line and the driving electrode between the first electrode portion and the piezoelectric actuator, impedance matching can be performed lightly, so that there is no insertion loss, and the Q value can be improved. The variable capacitor of the present invention is characterized in that a dielectric layer is provided between the second electrode portions facing the movable electrode. According to the present invention, the dielectric layer is provided between the second electrode portions for constituting the capacitor. Therefore, the electrostatic capacitance and the amount of change thereof can be increased. The η 务月、、、交交交交交交交交交交交交交交交交交交交交交交交交交交交交交交According to the invention, the movable electrode of the square-side is connected to the ground electrode to suppress the floating capacity. The present invention is characterized in that it is electrically separated from the boundary between the second electrode portion and the second electrode portion of the movable electrode. According to the present invention, since the movable electrode of one of the electrodes is electrically separated from the boundary between the second and second portions of the i-th electrode portion, the signal that is rotated in the second electrode portion of the other one passes through the second electrode portion. Finally, the other party = the second power = the end of the section 'has not reflected here, reducing the loss of the input (insertion loss). The variable capacitor of the present invention is characterized in that it is electrically actuated by the entrainment of the movable electrode: device 俾:: a voltage applied to the movable electrode is applied to the electrode to be close to == piezoelectrically actuated ~ In the foregoing, a voltage application device can be described, and a voltage application 20 1258778 is applied to the movable electrode. According to the present invention, by the driving of the piezoelectric actuator, in the approaching state, the electrostatic attraction force generated between the movable electrodes is applied to the movable electrode, and the pair is reduced and reduced. The distance is further the manufacturing method of the variable capacitor of the present invention. Driving the electric actuator to move the electrode in a movable state:,:= borrowing 10 15 20 : the system includes the following steps: forming a plurality of the foregoing steps on the substrate: an electric actuator; a step of forming a movable electrode having an ith electrode portion 电极 electrode portion; forming a sacrificial layer for forming a gap between the movable electrodes; removing the sacrificial layer; and removing a plurality of the foregoing pressures The end of the electric actuator and the front 1 = ==1 electrode particles (4) (4) minutes «The board is cut away according to the invention, the pole can be easily formed on the same substrate and used to drive the movable electrode Piezoelectric actuator. The method of manufacturing the variable capacitor of the present invention, wherein the variable capacitor is driven to move the electrode in a state of being movable to include a step of τ Forming a front-end; electro-actuating step on the substrate; forming a movable electrode having an i-th electrode portion and a second electrode portion on the substrate; forming a dielectric body between the movable electrodes = step; forming - using the aforementioned The movable electrode is the same as before and before a step of forming a sacrificial layer between the layers of the electric body; a step of removing the front (10) layer; and removing the end portion of the foregoing plurality of piezoelectric actuators and the first 10 U58778 " The portion other than the end portion of the portion is cut off by the aforementioned substrate. The handle can be easily formed on the same substrate in accordance with the present invention. The movable actuator is used to drive the piezoelectric actuator of the movable electrode and the pair of movable dielectric layers. The variable capacitor k of the present invention is manufactured in a square shape: the step of removing and the preceding cutting step are simultaneously performed. The tooth, the present portion can be removed at the same time as the removal step of removing the sacrificial layer and the cutting step of cutting off the end portion of the outer movable electrode and the piezoelectric actuator from the substrate, thereby improving work efficiency. According to the present invention, a variable capacitor can be provided, and the impact resistance is good, and the structure can also increase the electrostatic capacity, and the ratio of the electrostatic capacity can be increased, and the h can be increased. The fine adjustment of each amount of the pen. Further, 15 = is electrically separated from the piezoelectric actuator, and the configuration of the torsion bar in which the series resistance is caused becomes a special (second electrode portion) to ensure that the wide to the valley portion is obtained. High Q value. According to the present invention, the electric circuit can be electrically formed into a shape in which the substrate is floated in the air, and the surrounding portion is constructed to obtain a high second, thereby eliminating the dielectric constant of the substrate or the like. According to the present invention, the boundary between the one woven $ and the second electrode portion is configured as an energy loss of a signal input from the outside to the first electrode portion (interpolation, thereby preventing further, according to the present invention, constructed as: The driving force of the electric actuator makes 11 1258778 5 10 15 20 a pair of movable electrodes close to each other, and when a pair of movable electrode gates are pressed, the electrostatic attraction generated between the pair of movable electrodes can be utilized. ^ The distance between the two electrodes can be further reduced, and the larger electrostatic device II ® and the larger electrostatic capacitance can be obtained. Moreover, the driving of the piezoelectric actuator makes the electrode close to each other. In the following, the electrostatic attraction force is generated, so that a small driving voltage can be generated, and a large electrostatic attraction force is generated. [Embodiment] Referring to the drawings showing the embodiments of the present invention, the present invention is specifically described. Implementation. (Embodiment 1 embodiment) Fig. 3 is a perspective view of a variable capacitor according to a first embodiment; Fig. 4 is an exploded perspective view. In the figure, reference numeral 21 is formed by 矽, immersion, and the like. A substrate is provided with a cross-shaped opening at the center of the substrate 21, and an insulating layer 23 is provided on the upper surface of the conductor substrate 21. In the figure, reference numerals 35 and 37 are respectively formed by A1 (aluminum), and the upper portion is movable. The lower movable electrode 35 is composed of the end portion side line portions 35a and 35a which are the third Z electric power and the second electrosemis unit 35b as the second electrode unit, and the end portion of one of the line portions 35a is used. The signal pad 45 of the input signal of the high frequency signal source (not shown) of the J private valley portion, the end portion of the line portion 35a of the other phase is connected to the insulating layer, and the ground electrode 44 is electrically separated. On its equal end, and with the 35 series supported on the substrate η, except for the lower part of the Y-shaped electrode, the rest of the Y-electrode is located on the opening 40. Further, the upper FT of the FT moving electrode 37 is Line as the 1% pole and located on both ends, /a and as the 2nd

12 〜《778 電極部且位於中央的恭6 部、电各器部37b所構成，且兩方之線路上部“7電:=都連接於接地電極44。在其等端部上， ° ，、支撐於基板21，且除其等端部外之上部 5 可動=37之其餘部相位於開口4〇上。 '、等下柯動電極35及上部可動電極37係與基板21 之開口 40配合，而脱里丄配置成十字狀者，下部可動電極35之 35b與上部可動電極37之電容器部37b係隔著空凡層而相對者。在該相對之電容器部35b及電容器部讲上係作為包谷$之用。此外，相互呈電性分離狀態之下部可動電極35及上部可動電極37皆可在由接地浮上之狀態下使用者’由抑制浮動容量之目的來看，亦可將上部可動電極37連接於接地電極44。下部可動電極35及上部可動電極37係各以4個下部可動電極用致動器27a、27b、27c、27d及上部可動電極用致動器29a、29b、29c、29d予以驅動。其等下部可動電極用致動器27a〜27d及上部可動電極用致動器29a〜2卯係面向於基板21之開口 40。下部可動電極用致動器27(在說明 20 1個下部可動電極用致動器時，只使用參考符號27為代表) 及上部可動電極用致動^§ 29(在說明1個上部可動電極用致動裔時’只使用參考符號29為代表）係一種壓電致動器，其構造為由下往上依照絕緣層23、致動器用下部電極31、壓電層34、致動器用上部電極33疊層而成之單壓電晶片 (unimorph)型者。致動器用下部電極31係由Pt/Ti(始/欽)所構成，而致動器用上部電極33則由Pt所形成，每一電極 13 1258778 都是與下料動電極35及切可動電極37為互不相干之开趣由高頻信號源(圖中未示)輸入於讎之^虎係相下料動電極卩 5 10 15 20 = 35b透過空氣層，經由與電容器部说相對之上部可動 "極37的電谷為部別、線路部37a，而流入接地電極44。。口自層34的分極方向為相反之狀態，俾使於致動裔驅動時之移動方向為相反者。在下W可動電極用致動器π之致動器用上部電極幻上’由下部可動電極驅動用電源（圖中未示）向下部可動電極動塾42⑯加電麼，使下部可動電極％朝上部可動電極側私動’而在上部可動電㈣麟器Μ之致鮮用立電極33上，則由上部可動電極驅動用電源（圖中未口示）向: 部:動電極驅動塾43施加電壓，使上部可動電極37則朝力阿動电極35側移動，可各自獨立移動。藉此，驅動下 :可動電極用致動器27及/或上部可動電極用致動器^ 日寸’^文變上部可動電極37(電容器部叫與下部可動電極 35(電容器部35b)間之距離，可獲得預期之靜電容量。 “在本發明中，有來自高頻信號源之信號流動之線路部龟各杰邛、與用以驅動致動器之驅動電極呈電性分離之狀您。援此，線路部及電容器部不與致動器中之壓電層（高黾)相接觸，且因為周圍是空氣，所以不會有介電損失，且可提高Q值。第5圖係顯示第3圖之b_b線及C、C 、、象處之剖面。下部可動電極35之線路部35a及上部可動電 14 1258778 極37之線路部37a係構造成被連接於接地電極44之致動器用下部電極31夾於其中者。即，其等線路部35a及37a 係形成一 CP\V型線路，調整致動器用下部電極31及線路部35a或37a之間隔w：[、及線路部35a或37a之寬度w2， 5令線路部35a或37a之阻抗為5〇ω時，便不會有挿入損失。其次’參考第6圖及第7圖，說明具有上述結構之可變電容器之製造方法。又，第6圖及第7圖中，是顯示第3 圖之A-A線處之剖面。藉LPCVD(低壓化學氣相沉積；L〇w Pressure chemical 10 Vapor Deposition)法，在以矽為材料之基板21上形成應力低之氮化矽層23a，之後依序形成Pt/Ti(諸如厚度〇.5// m/50nm)層31a、及以鈮酸鋰、鈦酸鋇、鈦酸鉛、鈦酸錐酸鉛、鈦酸鉍等為材料之壓電層34a(諸如厚度0.5//m)(第6(a) 圖）。 15 接著，藉微影技術之圖案化處理，由壓電層34a、Pt/Ti 層31a形成預定形狀之壓電層34及致動器用下部電極 31(第6〇)、6((：)圖）。此時之圖案化處理是採用（：：12/心(氯/ 氬）類氣體之RIE(反應式離子餘刻；Reactive I〇n Etching) 裝置或離子研磨裝置等等。 20 藉微影技術，在壓電層34上形成Pt製之致動器用上部電極33(第6(d)圖），並對氣化矽層進行圖案化，以得到絕緣層23(第6(e)圖）。又，對於絕緣層23，可利用氮化石夕層外，還可鍍法、熱氧化法及CVD法等形成之氧化矽層。 15 1258778 立其乂，在基板21上形成由A1構成且有預定形狀之下阿動吃極35(第7(f)圖）後，形成一由光阻材料構成且具有預疋幵/狀之犧牲層Μ(第了⑻圖），在與下部可動電極％相對之值置上，形成由A1構成且具有預定形狀之上部可動電 5 極 37(第 7(h)圖）。立著，對位於下部可動電極35、上部可動電極37、下部可動電極用致動器27及上部可動電極用致動器心周邊的基板21，由其背面藉函E (Deep Reactive 1〇 10 15 20 獻置進行姓刻，形成開口⑽(第糊）。藉該姓刻將除下部可動電極35、上部可動電極37之各線路部祝的端部、下部可動電極驗動器27及上料動電極月為29之各端部外其餘的部分切離基板U。此外，該廣理中之蝕刻氣體係使用諸扣之遮蔽則為総。化计心形成開〔且於下部可以製造可變最後，對犧牲層41進行關予以除去，動電極35與上部可動電極37間確保間隙仍，電容器（第7⑴圖）。 4夕’亦可與上述之製造順序相異驟後，首先除去犧牲層41後，/下邱^弟7〇1)圖之步了知+ 谩在下部可動電極35盥上部刊笔極37之卩__ 49，對基板Μ進彳^ :口 4〇者。又，作為犧牲層“之材料，除了上述光阻；，亦可利用_(氧化鎂〉等氧化物，此時之 1卜乙酸或硝酸即可。 X 要使用第8圖係顯示可變電容12 to "778 electrode part and located in the center of the 6th part, the electric part 37b, and the upper part of the line "7 electric: = are connected to the ground electrode 44. On the other end, °, Supported on the substrate 21, and the other portion of the upper portion 5 movable = 37 except for the opposite ends thereof is located on the opening 4A. ', the lower driving electrode 35 and the upper movable electrode 37 are engaged with the opening 40 of the substrate 21, In the case where the leeches are arranged in a cross shape, the lower movable electrode 35 35b and the upper movable electrode 37 capacitor portion 37b are opposed to each other via an empty layer. The opposing capacitor portion 35b and the capacitor portion serve as a valley. In addition, the lower movable electrode 35 and the upper movable electrode 37 can be electrically separated from each other, and the user can't reduce the floating capacity in the state of being floated by the ground, and the upper movable electrode 37 can also be used. It is connected to the ground electrode 44. The lower movable electrode 35 and the upper movable electrode 37 are each provided by four lower movable electrode actuators 27a, 27b, 27c, and 27d and upper movable electrode actuators 29a, 29b, 29c, and 29d. Drive. Its lower movable electricity The actuators 27a to 27d and the upper movable electrode actuators 29a to 29b face the opening 40 of the substrate 21. The lower movable electrode actuator 27 (when the 20 first movable electrode actuators are described) , using only the reference symbol 27 as a representative) and the upper movable electrode for actuation 29 (indicating that only one of the upper movable electrodes is used by the reference symbol 29) is a piezoelectric actuator. The unimorph type is formed by laminating the insulating layer 23, the actuator lower electrode 31, the piezoelectric layer 34, and the actuator upper electrode 33 from the bottom to the top. The lower electrode 31 for the actuator It is composed of Pt/Ti (starting/chi), and the upper electrode 33 for the actuator is formed by Pt, and each electrode 13 1258778 is independent of the lower moving electrode 35 and the cutting movable electrode 37. Interested by a high-frequency signal source (not shown), input into the 虎^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ The valley is the part, the line portion 37a, and flows into the ground electrode 44. The mouth is directed from the polarization direction of the layer 34. In the opposite state, the direction of movement when the activist is driven is reversed. In the lower W movable actuator π actuator, the upper electrode is uttered by the lower movable electrode driving power supply (not shown) When the lower movable electrode 4116 is energized, the lower movable electrode % is moved to the upper movable electrode side, and the upper movable electrode (the fourth) is used for the fresh vertical electrode 33, and the upper movable electrode is driven by the upper movable electrode. (not shown in the drawing) To: Part: A voltage is applied to the movable electrode driving port 43, and the upper movable electrode 37 is moved toward the force moving electrode 35 side, and can be independently moved. Thereby, the movable electrode actuator 27 and/or the upper movable electrode actuator are driven between the capacitor portion and the lower movable electrode 35 (capacitor portion 35b). With the distance, the desired electrostatic capacity can be obtained. "In the present invention, there is a line from the high-frequency signal source that flows the signal to the turtle, and the drive electrode for driving the actuator is electrically separated. Accordingly, the line portion and the capacitor portion are not in contact with the piezoelectric layer (sorghum) in the actuator, and since there is air around, there is no dielectric loss and the Q value can be increased. Fig. 5 shows The line b-b of Fig. 3 and the cross section of C, C, and the image. The line portion 35a of the lower movable electrode 35 and the line portion 37a of the upper movable electrode 14 1258778 electrode 37 are configured to be connected to the actuator of the ground electrode 44. The lower electrode 31 is sandwiched therebetween. That is, the line portions 35a and 37a form a CP\V type line, and the interval w between the lower electrode 31 for the actuator and the line portion 35a or 37a is adjusted: [, and the line portion 35a or When the width of the 37a is w2, 5, the impedance of the line portion 35a or 37a is 5 〇 ω, There will be an insertion loss. Next, a method of manufacturing the variable capacitor having the above structure will be described with reference to FIGS. 6 and 7. Further, in FIGS. 6 and 7, a section showing the line AA of FIG. 3 is shown. A low-stress tantalum nitride layer 23a is formed on the substrate 21 made of tantalum by LPCVD (L低压w Pressure Chemical 10 Vapor Deposition) method, and then Pt/Ti (such as thickness) is sequentially formed. 〇.5 / / m / 50nm) layer 31a, and piezoelectric layer 34a (such as thickness 0.5 / / m) made of lithium niobate, barium titanate, lead titanate, lead titanate, barium titanate or the like (Fig. 6(a)). 15 Next, the piezoelectric layer 34 of a predetermined shape and the lower electrode 31 for the actuator are formed by the piezoelectric layer 34a and the Pt/Ti layer 31a by the patterning process of the lithography technique. 6〇), 6((:)图). The patterning process at this time is a RIE (Reactive I〇n Etching) device using (::12/heart (chlorine/argon) gas or An ion polishing apparatus or the like. 20 An upper electrode 33 for an actuator made of Pt is formed on the piezoelectric layer 34 by the lithography technique (Fig. 6(d)), and the vaporized tantalum layer is patterned. The insulating layer 23 is obtained (Fig. 6(e)). Further, as the insulating layer 23, a ruthenium oxide layer formed by a plating method, a thermal oxidation method, a CVD method, or the like may be used. Thereafter, after the substrate 21 is formed of A1 and has a predetermined shape under the movable electrode 35 (Fig. 7(f)), a sacrificial layer composed of a photoresist material and having a pre-twist/shape is formed. (Fig. 8), a value corresponding to the lower movable electrode % is formed, and a movable electric 5 pole 37 having a predetermined shape and having a predetermined shape is formed (Fig. 7(h)). The substrate 21 located around the lower movable electrode 35, the upper movable electrode 37, the lower movable electrode actuator 27, and the upper movable electrode actuator is stood by the back E (Deep Reactive 1〇10 15). 20 Deploying the last name to form an opening (10) (the first paste), by which the end portion of the lower movable electrode 35, the upper movable electrode 37, the lower movable electrode detector 27, and the upper moving body are removed. The remaining portion of each end of the electrode month 29 is cut away from the substrate U. In addition, the etching gas system in the wide-area uses the buckle to block the 総. The chemical core is formed open (and the lower portion can be made variable last) The sacrificial layer 41 is removed, and the gap between the movable electrode 35 and the upper movable electrode 37 is ensured, and the capacitor is still present (Fig. 7(1)). The fourth layer may be different from the above-described manufacturing sequence, and the sacrificial layer 41 is first removed. After, the next Qiu ^ brother 7 〇 1) Figure step know + 谩 in the lower movable electrode 35 盥刊刊刊 37 37 37 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Further, as the material of the sacrificial layer, in addition to the above-mentioned photoresist, an oxide such as _(magnesium oxide) may be used, and in this case, acetic acid or nitric acid may be used. X is to be used.

淼之製造方法的變形例。該變 16 U58778 形例之刖+段的製造步驟係 %糸舁上述之形態（第6(a)圖〜第7(f) 圖)同樣，形成由與基板21 ^ 宏^ 汉丄冋一之材料的矽構成且具有預 ==生:41(第8_)，且在與下部可動電極35相 ^置切成-具有預定形狀且由ai構成之上部極37(第8(b)圖）。电 10 15 道，使用諸如SF6氣體由基板21之表面側同時對犧 :二=21進行_，形成空腔47(第_)。藉 :*下柯動電極35、上部可動電極37之各線路部 a、37a之端部、下部可動電極用致動器u及上部可動電極用致動$ 29之各端部之外的其餘部分切離基板η者係與上述之形_樣，由基板21之表面_行_，因此不像上述形怨般形成開口，而形成空腔47。 ^藉該變形例所製造之可變電容器之分解立體圖示於第9圖。在基板21之中央部設置十字狀空腔47。此外，在第3圖、第4圖同-部分附上同—標號，並省略其等說明。 (第2實施形態）第1〇圖係第2實施形態之可變電容器之分解立體圖，第11圖及第12圖係顯示該可變電容器之製造步驟之剖視圖。在第2實施形態中，下部可動電極35、上部可動電極 37、下部可動電極用致動器27及上部可動電極用致動器29 之周邊中’在下部可動電極35、上部可動電極37及絕緣層 23與基板21間具有空間5〇。又，基板21不是由矽製造，則是由玻璃、藍寶石、氧化鋁、玻璃陶瓷、坤化鉀等之材 17 1258778 少成。除其等之外的結構係與第1實施形態同樣，對同 —部分付上同一標號。例如以玻璃為材料之基板21上，藉濺鍍法形成由矽構成之第2犧牲層51後，與第1實施形態同樣，依次形成氣化石夕層23a、Pt/Ti層3la、壓電層Ma(第11(a)圖）。接著， 14第1實施形態同樣，得到預定形狀之壓電層34、致動器用下部電極31、致動器用上部電極33及絕緣層23(第11(b) 〜U(e)圖）。A modification of the manufacturing method of the crucible. The manufacturing step of the 16 段 + segment of the variation 16 U 587 78 is the same as the above-described form (6 (a) to 7 (f)), and is formed by the substrate 21 ^ The crucible of the material has a pre-==birth: 41 (8th_), and is cut into a predetermined shape with the lower movable electrode 35 and constitutes an upper pole 37 by ai (Fig. 8(b)). The electric circuit 10 15 is formed by using, for example, SF6 gas from the surface side of the substrate 21 at the same time as the sa: 2 = 21 to form the cavity 47 (the _). By: * the lower actuator electrode 35, the end portions of the respective line portions a, 37a of the upper movable electrode 37, the lower movable electrode actuator u, and the upper movable electrode for the rest of the end portion of the actuator 29 The cut-off substrate η is shaped like the above, and is formed by the surface_row_ of the substrate 21, so that the cavity 47 is formed without forming an opening like the above-mentioned form. An exploded perspective view of the variable capacitor manufactured by the modification is shown in Fig. 9. A cross-shaped cavity 47 is provided at a central portion of the substrate 21. In addition, the same reference numerals are attached to the same portions in the third and fourth drawings, and the description thereof will be omitted. (Second Embodiment) Fig. 1 is an exploded perspective view showing a variable capacitor of a second embodiment, and Figs. 11 and 12 are cross-sectional views showing a manufacturing step of the variable capacitor. In the second embodiment, the lower movable electrode 35, the upper movable electrode 37, the lower movable electrode actuator 27, and the upper movable electrode actuator 29 are in the vicinity of the lower movable electrode 35, the upper movable electrode 37, and the insulating body. There is a space 5 层 between the layer 23 and the substrate 21. Further, the substrate 21 is not made of niobium, but is made of glass, sapphire, alumina, glass ceramics, potassium hydride, etc. 17 1258778. The same components as those of the first embodiment are denoted by the same reference numerals. For example, after the second sacrificial layer 51 made of tantalum is formed on the substrate 21 made of glass, the gasification layer 23a, the Pt/Ti layer 31a, and the piezoelectric layer are sequentially formed in the same manner as in the first embodiment. Ma (Fig. 11(a)). Then, in the same manner as in the first embodiment, the piezoelectric layer 34 of the predetermined shape, the lower electrode 31 for the actuator, the upper electrode 33 for the actuator, and the insulating layer 23 (Fig. 11(b) to U(e)) are obtained.

1〇其次’將具有預定形狀且由A1構成之下部可動電極 35形成在第2犧牲層51上後（第12(f)圖），在全部區域上形成由光阻材料構成之犧牲層41(第12(g)圖），在與下部可動電極35相對之位置上，形成具有預定形狀且由A1構成之上部可動電極37(第12(h)圖）。 15 接著，對犧牲層41蝕刻予以除去，在下部可動電極 35與上部可動電極37間確保間隙49(第12(i)圖），又，將Next, after the lower movable electrode 35 is formed on the second sacrificial layer 51 by a predetermined shape and formed of A1 (Fig. 12(f)), a sacrificial layer 41 made of a photoresist material is formed on the entire region ( In the 12th (g)th view, the upper movable electrode 37 is formed by A1 at a position facing the lower movable electrode 35 (Fig. 12(h)). 15 Next, the sacrificial layer 41 is removed by etching, and a gap 49 is secured between the lower movable electrode 35 and the upper movable electrode 37 (Fig. 12(i)).

第2犧牲層51蝕刻予以除去，在基板21與下部可動電極 35 及繞緣層23間確保空間50，製造可變電容器（第12⑴ 圖）。此外，亦可令該犧牲層41及第2犧牲層51為同一材扣’、同日寸進行犧牲層41的钱刻及第2犧牲層51之钱刻者。在第2實施形態中，藉第2犧牲層51之蝕刻，可使 F可動笔極35由基板21浮在空中，因此沒有對基板21 、^餘刻之必要，便可使作為基板21之用的材料種類增例如’丨電常數極低、難以钱刻之玻璃陶瓷等之材料亦 σ仏為基板21之用者。藉此，可使q值更進一步提昇者。 18 1258778 (第3實施形態）第13圖係第3實施形態之可變電容器（只有可動電極及壓電致動器）之分解立體圖；第14圖及第15圖係顯示該可變電容器之製造步驟之剖視圖。 5 在第3實施形態中，下部可動電極35(電容器部35b) 與上部可動電極37(電容器部37b)間設有介電體層46。其餘構成係與第1實施形態同樣，對同一部分付與同一標號，並省略其等說明。該介電體層46，如第13圖所示，亦可設於上部可動 10 電極37(電容器部37b)，雖未於圖中顯示，亦可設於下部可動電極35(電容器部35b)側者。藉介電體層46之設置，可增加可動部分的質量，固然稍微引起共振頻率的降低或可動速度之降低，但如後述，可大幅增加靜電容量及其變化率0 15 第16圖係顯示介電體層46之效果的圖。如第16(a) 圖所示，針對在上部可動電極37之電容器部37b側設置介電體層46進行說明。令介電體層46之厚度為dl、形成在介電體層46與下部可動電極35之電容器部35b間之空氣層的厚度為d2時，電容器部37b與電容器部35b間之距離 20 d 則為：d=dl + d2。第16(b)圖係一線圖，顯示將電容器部35b及/或電容器部37b予以移動，改變空氣層之厚度d2時之靜電容量C 之變化者。令電容器部35b及電容器部37b為正方形（一邊·· 230//m)，且初始狀態之電極間距離d及空氣層之厚度 1258778 d2 各為 d=0.75//m 及 d2=〇.3//m(d2/d=0.4)，介電體層 46係使用介電損失小之材料的A1203 (氧化鋁）(介電常數ε = 10)。又，只有不設置如此之介電體層之點上為相異之比較例中之靜電容量C的變化亦一併顯示在第16(b)圖中。 5 如第16(b)圖所示，以設有介電體層46之本發明例之可變電容器而言，在初始狀態中為約1.36pF、電容器部35b 與介電體層46相接之狀態下則具有約10.4pF之靜電容量，該變化率約為7.6倍。如此設置介電體層46，便可將靜電容量及其可變範圍大增。 10 第14圖係剖視圖，顯示第3實施形態之可變電容器之製造步驟的一種形態（將介電體層46設於上部可動電極 37(電容器部37b)之側）者。前半段的步驟係與前述之第工實施形態的步驟（第6(a)圖至第7(g)圖）相同。藉微影技術，在犧牲層41上對以Al2〇3為材料之介電 15體層46實施圖案化（第14(a)圖），在與下部可動電極35相對之位置上，形成由A1構成且具有預定形狀之上部可動電極37(第14(b)圖）。接著，對下部可動電極35、上部可動電、下部可動電極用致動器27及上部可動電極用致動器 2〇 9之周邊的基板21，由其背面，藉E)RIE裝置進行蝕刻，於成開口 40(第14(c)圖）。最後將犧牲層41蝕刻予以除去， :下部可動電極35與介電體層46間確保間隙49，製造可欠電容器（第l4(d)圖）。第15圖係剖視圖，顯示第3實施形態之可變電容器衣造步驟的另-形態（將介電體層#設於下部可動電極 20 1258778 35(電容器部35b)側)者。前半段的步驟係與前述之第工實施形態的步驟（第6(a)圖〜第7(f)圖）相同。藉微影技術，在下部可動電極35上訝以八丨2^為材料之介電體層46實施圖案化（第15⑷圖）。使由光阻材料或 5 Mg〇構成之犧牲層41形成為預定形狀（第15(b)圖），在與下部可動電極35相對之位置，形成具有預定形狀且由^ 構成之上部可動電極37(第15(幻圖）。接著，將位於下部可動電極35、上部可動電極37、下部可動電極用致動器27 及上部可動電極用致動器29之周邊的基板21，由其背面， 10藉DRIE裝置進行蝕刻，形成開口 40(第15(d)圖）。最後，藉蝕刻除去犧牲層41，以於介電體層46與上部可動電極 37間確保間隙49，製造可變電容器（第15(e)圖）。此外，亦可和上述之第14圖及第15圖之製造順序相異，在第14(b)圖、第15(c)圖之步驟之後，先將犧牲層41 15 除去，確保間隙49後，再對基板21進行蝕刻，形成開口 40者。又，對於該第3實施形態，亦可如同前述之形態（參考第8圖），令犧牲層41之材料與基板21相同，對犧牲層 41及基板21依序或同時由基板21之表面側進行蝕刻者。 (第4實施形態） 2〇第17圖係顯示第4實施形態，第17(a)圖係第4實施形態之可變電容器之俯視圖；第17(b)圖係第17(a)圖之D 部的擴大圖。在第4實施形態中，一方的線路部35a與信號墊45 相連接之下部可動電極35中，其電容器部35b與另一方之 W8778 線路部35a係呈電性分離之纟丁如之狀恶。即，由信號墊45來看， 4可動電極35係越過下部可私〇7 , 丨了動電極％與上部可動電極 07相對而構成電容器之部分 ^ , 刀（包合态部35b及電容器部37b 之相對部分）之處，電性分籬成故加刀離成兩者。又’呈分離狀態之線路崢35a亦可與接地電極44相鱼 44相連接，而作接地電位之用。在第4實施形態中，由作缺载 — 由k唬墊45進入之信號係經由 —方之線路部35a而通過電容器部现後到達與另一方之線路部35a的與信號墊45相反側之端，在此沒有反射之情 10The second sacrificial layer 51 is removed by etching, and a space 50 is secured between the substrate 21 and the lower movable electrode 35 and the peripheral layer 23 to manufacture a variable capacitor (Fig. 12(1)). Further, the sacrificial layer 41 and the second sacrificial layer 51 may be made of the same material buckle, and the money of the sacrificial layer 41 and the money of the second sacrificial layer 51 may be performed in the same day. In the second embodiment, the F movable pen electrode 35 can be floated in the air by the substrate 21 by the etching of the second sacrificial layer 51. Therefore, the substrate 21 can be used as the substrate 21 without the need for the substrate 21. The type of material is increased, for example, a material having a very low electric constant and a glass ceramic which is difficult to be used is also used as the substrate 21. Thereby, the q value can be further improved. 18 1258778 (Third Embodiment) Fig. 13 is an exploded perspective view showing a variable capacitor (only a movable electrode and a piezoelectric actuator) according to a third embodiment; and Figs. 14 and 15 show the manufacture of the variable capacitor. A cross-sectional view of the steps. In the third embodiment, the dielectric layer 46 is provided between the lower movable electrode 35 (capacitor portion 35b) and the upper movable electrode 37 (capacitor portion 37b). The same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. The dielectric layer 46 may be provided on the upper movable 10 electrode 37 (capacitor portion 37b) as shown in Fig. 13, and may be provided on the lower movable electrode 35 (capacitor portion 35b) side, although not shown in the drawing. . By the arrangement of the dielectric layer 46, the mass of the movable portion can be increased, although the resonance frequency is lowered slightly or the movable speed is lowered. However, as will be described later, the electrostatic capacity and the rate of change thereof can be greatly increased. A diagram of the effect of the body layer 46. As shown in Fig. 16(a), the dielectric layer 46 is provided on the side of the capacitor portion 37b of the upper movable electrode 37. When the thickness of the dielectric layer 46 is dl and the thickness of the air layer formed between the dielectric layer 46 and the capacitor portion 35b of the lower movable electrode 35 is d2, the distance 20d between the capacitor portion 37b and the capacitor portion 35b is: d=dl + d2. Fig. 16(b) is a one-line diagram showing changes in the electrostatic capacitance C when the capacitor portion 35b and/or the capacitor portion 37b are moved to change the thickness d2 of the air layer. The capacitor portion 35b and the capacitor portion 37b are square (one side · 230 / / m), and the inter-electrode distance d in the initial state and the thickness of the air layer 1258778 d2 are d = 0.75 / / m and d2 = 〇. 3 / /m (d2/d = 0.4), the dielectric layer 46 is made of A1203 (alumina) (dielectric constant ε = 10) of a material having a small dielectric loss. Further, only the change in the electrostatic capacitance C in the comparative example in which the dielectric layer is not provided is also shown in Fig. 16(b). As shown in Fig. 16(b), the variable capacitor of the present invention having the dielectric layer 46 is in a state of about 1.36 pF in the initial state, and the capacitor portion 35b is in contact with the dielectric layer 46. The lower portion has an electrostatic capacity of about 10.4 pF, which is about 7.6 times. By disposing the dielectric layer 46 in this manner, the electrostatic capacity and its variable range can be greatly increased. Fig. 14 is a cross-sectional view showing one embodiment of the manufacturing process of the variable capacitor of the third embodiment (the dielectric layer 46 is provided on the side of the upper movable electrode 37 (capacitor portion 37b)). The steps of the first half are the same as the steps of the above-described first embodiment (Fig. 6(a) to Fig. 7(g)). The dielectric 15 body layer 46 made of Al 2 〇 3 is patterned on the sacrificial layer 41 by lithography (Fig. 14(a)), and formed at A position opposite to the lower movable electrode 35 by A1. And having a predetermined shape upper movable electrode 37 (Fig. 14(b)). Then, the substrate 21 around the lower movable electrode 35, the upper movable electrode, the lower movable electrode actuator 27, and the upper movable electrode actuator 2〇9 is etched by the back surface by an E) RIE device. An opening 40 (Fig. 14(c)). Finally, the sacrificial layer 41 is etched and removed, and a gap 49 is secured between the lower movable electrode 35 and the dielectric layer 46 to manufacture an undercapacitor (Fig. 14(d)). Fig. 15 is a cross-sectional view showing another embodiment of the variable capacitor coating step of the third embodiment (the dielectric layer # is provided on the lower movable electrode 20 1258778 35 (capacitor portion 35b) side). The steps of the first half are the same as the steps of the above-described first embodiment (Fig. 6(a) to Fig. 7(f)). By the lithography technique, the dielectric layer 46, which is made of a material of the lower movable electrode 35, is patterned (Fig. 15(4)). The sacrificial layer 41 composed of a photoresist material or 5 Mg 形成 is formed into a predetermined shape (Fig. 15(b)), and at a position opposed to the lower movable electrode 35, a movable electrode 37 having a predetermined shape and composed of an upper portion is formed. (Fifteenth (phantom). Next, the substrate 21 located around the lower movable electrode 35, the upper movable electrode 37, the lower movable electrode actuator 27, and the upper movable electrode actuator 29 is provided on the back surface thereof. Etching is performed by a DRIE device to form an opening 40 (Fig. 15(d)). Finally, the sacrificial layer 41 is removed by etching to ensure a gap 49 between the dielectric layer 46 and the upper movable electrode 37 to manufacture a variable capacitor (15th) (e) Fig.) In addition, it may be different from the manufacturing order of Figs. 14 and 15 described above. After the steps of Figs. 14(b) and 15(c), the sacrificial layer 41 15 is first introduced. After the gap 49 is secured, the substrate 21 is etched to form the opening 40. Further, in the third embodiment, the material of the sacrificial layer 41 and the substrate 21 may be formed in the same manner as described above (refer to Fig. 8). Similarly, the sacrificial layer 41 and the substrate 21 are sequentially or simultaneously formed by the surface of the substrate 21. (Embodiment 4) Fig. 17 shows a fourth embodiment, and Fig. 17(a) is a plan view of a variable capacitor of the fourth embodiment; and Fig. 17(b) is a 17th (a) An enlarged view of the D portion of the figure. In the fourth embodiment, one of the line portions 35a is connected to the signal pad 45, and the lower portion of the movable electrode 35 is formed by the capacitor portion 35b and the other W8778 line portion 35a. The electrical separation is similar to that of the crucible. That is, from the signal pad 45, the movable electrode 35 is passed over the lower portion, and the movable electrode % is opposite to the upper movable electrode 07 to form a portion of the capacitor. Where the knives (the opposite portions of the clad portion 35b and the capacitor portion 37b) are electrically separated, the knives are separated from each other by the knife. The line 峥35a in the separated state may also be in phase with the ground electrode 44. In the fourth embodiment, the signal entered by the k-pad 45 is passed through the capacitor portion and then reaches the other line portion. The end of 35a opposite to the signal pad 45, there is no reflection here 10

事’可將如此反射信號料，因此可防止輸人信號損失。里 (第5實施形態） ♦第18圖係第5實施形態之可變電容器之俯視圖。如第18圖所示’在信號墊45及接地電極44間設有一電源電路仙，藉此可在信號墊45(下部可動電極叫與接地電極 15 44(上部可動電極37)間施加電壓者。The event can reflect the signal so that the loss of the input signal can be prevented. (Embodiment 5) ♦ Fig. 18 is a plan view showing a variable capacitor of a fifth embodiment. As shown in Fig. 18, a power supply circuit is provided between the signal pad 45 and the ground electrode 44, whereby a voltage can be applied between the signal pad 45 (the lower movable electrode is called the ground electrode 1544 (the upper movable electrode 37).

第5實施形態係與用以調整下部可動電極35(電容器部35b)與上部可動電極37(電容器部37b)間之間隔之方法有關。驅動下部可動電極用致動器27及/或上部可動電極用致動II 29’將電容器部35b與電容器部別間之間隔縮 20小後，接著藉電源電路48在下部可動電極35與上部可動電極37之間施加電壓，藉兩電極間所產生之靜電引力，可進一步將兩電極間之距離縮小。依此在第5貫施形悲中，構建成進行壓電致動器驅動及静電致動器（弓I力）驅動之兩階段的距離控制，可使兩可 22 12响 78 動電極進-步接近，可獲得靜•量更大的變化者。在壓電致動器中，使兩可動電極接近之狀態下產生靜電引力，可展現獲得較大之靜電容量及空b 里及奋堇變化之效果。又，藉壓電致動器，使兩可動電極相接说+…At 和得近之狀態下產生靜電引力，因此可以較小之驅動電壓’產生較大之靜電引力。此外’在上权料、中，下部可動電極用致動器27 10 15 20 及上部可動電極用致動器29為單壓電晶片型，但並不限於此。例如第刚圖所示之並聯式雙壓電晶片（bim〇rph)、或亦可為第19(b)圖所示之串聯式雙壓電晶片者。在第19⑷、 l9(b)圖中’在中間電極63之上、下設有如圖中所示之箭頭方向分極之壓電元件54a、54b。在壓電元件％上設置下部驅動電極53 ’在壓電元件細上則設有上部驅動電極 55。接著，如圖所不，藉施加直流電壓v，使雙壓電晶片 (bimorph)變形。令下部可動電極用致動器巧及上部可動電極用致動器29為雙壓電晶片型時，在上述之各實施形態中，便不需要與致動器用下部電極31相連接之絕緣層23。本發明並不限定於上述之各實施形態或變形例，亦可包括其餘各種實施形態或變形例在内。例如在上述之带能中，構建成驅動壓電致動器，以使兩可動電極間之距離L 或將可動電極與介電體層間之距離縮小（將靜電容量加大) 者，反之，亦可構建成：驅動壓電致動器，以將其等距離加大(將靜電容量縮小）者。此時，只要將單壓電晶片型壓電致動器變形方向反向顛倒即可。又，亦可將上述之實施3 悲或變形例中之可變電容器收容在陶瓷製容器中。此時， 23 1258778 藉電線或凸出部等連接構件，便可將設於容器之外部連接端子與設於基板21之信號墊45等之各種墊襯相連接者。【圖式簡單說明】第1(a)圖係顯示習知可變電容器之結構的剖視圖。 5 第1(b)圖係顯示習知可變電容器之結構的俯視圖。第2圖係顯示電容器之靜電容量及電極間距離之關係的線圖。第3圖係第1實施形態之可變電容器之立體圖。第4圖係第1實施形態之可變電容器之分解立體圖。 10 第5圖係第3圖之B-B線及C-C線處之剖視圖。第6(a)-6(e)圖係剖視圖，顯示第1實施形態之可變電容器之製造步驟者。第7(f)-7(j)圖係剖視圖，顯示第1實施形態之可變電容器之製造步驟者。 15 第8(a)-8(c)圖係剖視圖，顯示第1實施形態之可變電容器之製造步驟的變形例者。第9圖係第1實施形態之可變電容器之變形例的分解立體圖。第10圖係第2實施形態之可變電容器之分解立體圖。 20 第11(a)-11(e)圖係第2實施形態之可變電容器之製造步驟的剖視圖。第12(f)-12(j)圖係剖視圖，顯示第2實施形態之可變電容器之製造步驟者。第13圖係第3實施形態之可變電容器（只有可動電極 24 1258778 及壓電致動器）之分解立體圖。第14(a)-14(d)圖係剖視圖，顯示第3實施形態之可變電容器之製造步驟的一形態者。第15(a)-15(e)圖係剖視圖，顯示第3實施形態之可變 5 電容器之製造步驟的另一形態者。第16(a)圖係第3實施形態之可變電容器之概略結構圖。The fifth embodiment relates to a method for adjusting the interval between the lower movable electrode 35 (capacitor portion 35b) and the upper movable electrode 37 (capacitor portion 37b). Driving the lower movable electrode actuator 27 and/or the upper movable electrode actuation II 29' to reduce the interval between the capacitor portion 35b and the capacitor portion by 20, and then moving the lower movable electrode 35 and the upper portion by the power supply circuit 48 A voltage is applied between the electrodes 37, and the electrostatic attraction between the electrodes can further reduce the distance between the electrodes. According to this, in the fifth mode of sorrow, the two-stage distance control for driving the piezoelectric actuator and the electrostatic actuator (the bow force) is constructed, so that the two 12 12 loud 78 moving electrodes can be entered. - Steps are close, and you can get more static change. In the piezoelectric actuator, electrostatic attraction is generated in a state where the two movable electrodes are close to each other, and the effect of obtaining a large electrostatic capacity and a change in the air and the air can be exhibited. Further, by the piezoelectric actuator, the two movable electrodes are connected to each other to say that +...At and the electrostatic attraction force is generated, so that a small driving voltage can generate a large electrostatic attractive force. Further, the upper movable electrode actuators 27 10 15 20 and the upper movable electrode actuator 29 are of a unimorph type, but are not limited thereto. For example, a parallel bimorph (bim〇rph) as shown in Fig. 3 or a tandem bimorph shown in Fig. 19(b). In the 19th (4)th and 9th (b)th drawings, the piezoelectric elements 54a and 54b which are divided in the direction of the arrow as shown in the figure are provided above and below the intermediate electrode 63. The lower driving electrode 53' is provided on the piezoelectric element %, and the upper driving electrode 55 is provided on the piezoelectric element. Next, as shown in the figure, the bimorph is deformed by applying a DC voltage v. When the actuator for the lower movable electrode and the actuator for the upper movable electrode 29 are of the bimorph type, in the above embodiments, the insulating layer 23 connected to the lower electrode 31 for the actuator is not required. . The present invention is not limited to the above-described respective embodiments or modifications, and may include various other embodiments or modifications. For example, in the above-mentioned band energy, it is configured to drive the piezoelectric actuator such that the distance L between the movable electrodes or the distance between the movable electrode and the dielectric layer is reduced (the electrostatic capacity is increased), and vice versa. It can be constructed to drive a piezoelectric actuator to increase its distance (to reduce the electrostatic capacity). In this case, the deformation direction of the unimorph piezoelectric actuator may be reversed in reverse. Further, the variable capacitor in the above-described implementation or modification may be housed in a ceramic container. At this time, 23 1258778 can connect the external connection terminals provided in the container to the various pads of the signal pad 45 provided on the substrate 21 by means of a connecting member such as a wire or a projection. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1(a) is a cross-sectional view showing the structure of a conventional variable capacitor. 5 Figure 1(b) shows a top view of the structure of a conventional variable capacitor. Fig. 2 is a line graph showing the relationship between the electrostatic capacitance of the capacitor and the distance between the electrodes. Fig. 3 is a perspective view of a variable capacitor of the first embodiment. Fig. 4 is an exploded perspective view showing the variable capacitor of the first embodiment. 10 Fig. 5 is a cross-sectional view taken along line B-B and line C-C of Fig. 3. Fig. 6(a)-6(e) is a cross-sectional view showing the manufacturing steps of the variable capacitor of the first embodiment. Fig. 7(f)-7(j) is a cross-sectional view showing the manufacturing steps of the variable capacitor of the first embodiment. 15(a)-8(c) is a cross-sectional view showing a modification of the manufacturing procedure of the variable capacitor of the first embodiment. Fig. 9 is an exploded perspective view showing a modification of the variable capacitor of the first embodiment. Fig. 10 is an exploded perspective view showing the variable capacitor of the second embodiment. 20(a)-11(e) is a cross-sectional view showing a manufacturing step of the variable capacitor of the second embodiment. Fig. 12(f)-12(j) is a cross-sectional view showing the manufacturing steps of the variable capacitor of the second embodiment. Fig. 13 is an exploded perspective view showing the variable capacitor (only the movable electrode 24 1258778 and the piezoelectric actuator) of the third embodiment. Figs. 14(a)-14(d) are cross-sectional views showing one embodiment of the manufacturing steps of the variable capacitor of the third embodiment. 15(a)-15(e) is a cross-sectional view showing another embodiment of the manufacturing procedure of the variable 5 capacitor of the third embodiment. Fig. 16(a) is a schematic configuration diagram of a variable capacitor in the third embodiment.

第16(b)圖係顯示壓電致動器之變位及靜電容量之關係的線圖。 10 第17(a)圖係第4實施形態之可變電容器之俯視圖。第17(b)圖係第17(a)圖之D部中之擴大圖。第18圖係第5實施形態之可變電容器之俯視圖。第19(a)圖係顯示並聯式雙壓電晶片型之壓電致動器之圖。 15 第19(b)圖係顯示串聯式雙壓電晶片型之壓電致動器Fig. 16(b) is a line diagram showing the relationship between the displacement of the piezoelectric actuator and the electrostatic capacity. 10(a) is a plan view of a variable capacitor in the fourth embodiment. Figure 17(b) is an enlarged view of Part D of Figure 17(a). Fig. 18 is a plan view showing a variable capacitor of a fifth embodiment. Fig. 19(a) is a view showing a piezoelectric actuator of a parallel bimorph type. 15 Figure 19(b) shows a piezoelectric actuator of tandem bimorph type

之圖。【圖式之主要元件代表符號表】 11.. .可動電極用基板 12.. .壓電致動器 13.. .可動電極 14···軟焊墊 15.. .固定電極用基板 17…扭桿 21…勒反 23…絕緣層 31...致動器用下部電極 27,27\275,27〇,27丄..下部可動電極用致動器 16…固定電極 25 1258778 29,29a，29b，29c，29d …上部可動 42...下部可動電極驅動墊電極用致動器 43...上部可動電極驅動墊 33...致動器用上部電極 44…接地電極 34...壓電層 45...信號墊 35...下部可動電極 46…介電體層 37...上部可動電極 47…空腔 35a，37a…線路部(第1電極部） 48··.電源電路 35b，37b...電容器部(第2電極 49...間隙部） 50...空間 40···開口 51...第2犧牲層 41…犧牲層 26Picture. [Main component representative symbol table of the drawing] 11.. Movable electrode substrate 12.. Piezoelectric actuator 13.. Movable electrode 14··· Soft pad 15.. Fixed electrode substrate 17... Torsion bar 21...inverter 23...insulation layer 31...actuator lower electrode 27,27\275,27〇,27丄.. lower movable electrode actuator 16...fixed electrode 25 1258778 29,29a,29b , 29c, 29d ... upper movable 42... lower movable electrode drive pad electrode actuator 43... upper movable electrode drive pad 33... actuator upper electrode 44... ground electrode 34... piezoelectric layer 45...signal pad 35...lower movable electrode 46...dielectric layer 37...upper movable electrode 47...cavity 35a,37a...line portion (first electrode portion) 48··. power supply circuit 35b, 37b ...capacitor portion (second electrode 49 ... gap portion) 50 ... space 40 · opening 51 ... second sacrificial layer 41 ... sacrificial layer 26

Claims

1258778 拾、申請專利範圍： ['平㈣习賴. 軸_號案申請專利範圍修正本 94_2i日— 1.種可變電容器，係可使相對之電極移動者，包：基板； 5 可動電極，係具有第1電極部及第2電極部；及夕數壓電致動器，係用以驅動前述可動電極者· 、>、中岫述可動電極相對設置而構造成電容器，並將前述可動電極與信號墊導電連接；又，前述多數壓電致動器各自具有驅動電極及設於該 10 軸電極間之壓f元件，且前述㈣電極與前述可動電極為個別之個體。 2·如申請專利範圍帛1項之可變電容器’其中前述可動電極係具有前述第1電極部及前述第2電極部，且使前述可動電極呈上下設置者。 15 3.如中請專利範圍第1或2項之可變電容器，其中前述可動電極之第1電極部兩側設置前述壓電致動器，藉前述第1電極部及前述壓電致動器之驅動電極，構造成一 CPW型線路者。 4·如申請專利範圍第1《2項之可變電容器，其中前述可 2〇動電極之相對之前述第2電極部間設有介電體層者。 5·如申請專利範圍第1《2項之可變電容器，其中前述可動電極中之至少一方與接地電極相連接者。 6·如中請專利範圍第1《2項之可變電容器，其中前述可動電極之任一方的前述第1電極部與前述第2電極部間 ^^778 .....................·.-...........-................ 之境界部近旁係呈電性分離者。 7·〜種可變電容器，係包含有·· 可沿其相對方向移動之可動電極；及用以驅動前述可動電極之多數壓電致動哭. 施力Γ置具有1叫前述可動電極間施加健之❾ 俾構建成在於前賴電致動器之_ 極接近之狀態下，^ 使則述可動1 精則述電壓施加裝置前述可動電極間者。特電屋知加衣 101258778 Pick up, apply for patent scope: ['Ping (four) Xi Lai. Axis _ number application patent scope revision this 94_2i day - 1. Kind of variable capacitor, which can move relative to the electrode, package: substrate; 5 movable electrode, The first electrode portion and the second electrode portion are provided, and the eclipse piezoelectric actuator is configured to drive the movable electrode, and the movable electrode is disposed opposite to each other to form a capacitor, and the movable portion is movable The electrode is electrically connected to the signal pad; and each of the plurality of piezoelectric actuators has a driving electrode and a pressure f element provided between the 10-axis electrodes, and the (four) electrode and the movable electrode are individual members. 2. The variable capacitor of claim 1, wherein the movable electrode has the first electrode portion and the second electrode portion, and the movable electrode is placed up and down. The variable capacitor of the first or second aspect of the invention, wherein the piezoelectric actuator is provided on both sides of the first electrode portion of the movable electrode, and the first electrode portion and the piezoelectric actuator are provided The driving electrode is constructed as a CPW type line. 4. The variable capacitor according to the first aspect of the invention, wherein the dielectric layer is provided between the second electrode portions opposite to the movable electrode. 5. The variable capacitor of claim 1, wherein at least one of the movable electrodes is connected to the ground electrode. 6. The variable capacitor according to the first aspect of the invention, wherein the first electrode portion of the movable electrode and the second electrode portion are between ^ 778 .... ...........·.-..............-................ The vicinity of the realm is electrically Separator. a variable capacitor comprising: a movable electrode movable in a relative direction thereof; and a plurality of piezoelectrically actuated cryings for driving the movable electrode. The force applying device has a function of applying the first movable electrode between the electrodes The Jianzhi ❾ is constructed in a state in which the _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Special electric house knowing clothes 10

8· 一種可變電容器之製造方法，該可變電利範圍第1項所★己# 态係如申請專動者，該方法係包含有以下步驟，即：的㈣使電極移在基板上形成多數前述壓電致動器之· 15 電極形成具有第1電極部及第喻部之可動8. A method of manufacturing a variable capacitor, wherein the method of claim 1 is as claimed, wherein the method comprises the following steps: (4) moving the electrode on the substrate. Most of the electrodes of the piezoelectric actuator are formed to have a movable portion having a first electrode portion and a first portion.

形成-用以於前述可動電極步驟；战間隙之犧牲層之將前述犧牲層除去之除去步驟；及 20 將除前述多數前述壓電致動極之第1電極部之心〈、縣則述可動電離步驟。k㈣之外的部分由前述基板切離之切 9·一種可變電容器之製利範圍第4項所㈣變電容器係如申請專動者，該方法係包含有以下步驟，^祕動使電極移 28 1258778 在基板上形成多數前述壓電致動器之步驟；在前述基板形成具有第1電極部及第2電極部之可動電極之步驟；在前述可動電極間形成介電體層之步驟； 5 形成一用以於前述可動電極之任一方與前述介電體層間形成間隙之犧牲層之步驟；將前述犧牲層除去之除去步驟；及將除前述多數前述壓電致動器之端部及前述可動電極之第1電極部之端部之外的部分由前述基板切離之切 10 離步驟。 10.如申請專利範圍第8或9項之可變電容器之製造方法，其中前述除去步驟及前述切離步驟係同時進行者。Forming a step of removing the sacrificial layer from the sacrificial layer of the war gap; and removing the core of the first electrode portion of the plurality of piezoelectric actuators Ionization step. The portion other than k(4) is cut away from the substrate. 9. The profitable range of a variable capacitor is the fourth item. (4) The variable capacitor is as claimed in the application. The method includes the following steps: 28 1258778 a step of forming a plurality of the piezoelectric actuators on a substrate; a step of forming a movable electrode having a first electrode portion and a second electrode portion on the substrate; a step of forming a dielectric layer between the movable electrodes; 5 forming a step of forming a sacrificial layer between the movable electrode and the dielectric layer; removing the sacrificial layer; and removing the end portion of the piezoelectric actuator and the movable portion The portion other than the end portion of the first electrode portion of the electrode is cut away from the substrate. 10. The method of manufacturing a variable capacitor according to claim 8 or 9, wherein the removing step and the cutting step are performed simultaneously.